The present invention relates to liquid containers and more particularly to a system for virtually eliminating fuel leakage from failed component parts and significantly reducing fuel spillage during normal operations from fuel tanks mounted on small tractors.
In conventional small tractors, the fuel tank was usually positioned between the tractors rear wheels under the rear fender deck. The tank filler neck conventionally protruded above the level of the fender deck and extended at an angle rearwardly away from the operator's seat. These conventional tanks employed vented necks and caps.
Conventionally, the shut-off valve connecting the tank to the engine was located in an area under the fender deck such that approximately ninety percent of the fuel contained in a full tank was above the level of the shut-off valve. This conventional location made servicing the shut-off valve difficult and time consuming. Since the shut-off valve was conventionally attached to the tank by a bushing, bushing failure, due to the shut-off valves location in the tank, allowed up to ninety percent of a full fuel tank to leak therefrom. Further, when servicing the shut-off valve, with the conventional tank construction, it was necessary to either drain the tank or remove the fuel tank from the tractor prior to servicing the shut-off valve. Also during shut-off valve servicing the mesh screen filter, which is part of the conventional shut-off valve assembly, was usually damaged. Finally, because of poor operator accessability due to the shut-off valves conventional location under the rear fender deck, normal operation of the valve was difficult and slow.
Additionally, with conventional fuel tanks, due to operators over filling the tank, significant spillage problems developed. For example, it is well known that increased temperature causes volume expansion of fuel in the tank. Even when the conventional tank is filled to the proper level, it was not unusual with a dramatic temperature change for fuel to flow out of the conventional vented gas cap and filler neck and accumulate on the tank and other tractor surfaces. Even moderate temperature change was sufficient, with an over filled conventional tank, for fuel to flow out of the conventional vented gas tank and filler neck and accumulate on the various tractor surfaces. Occasionally, even with a properly filled tank, and moderate to dramatic temperature change, it was not unusual for fuel to flow out of the cap and filler neck when the vehicle was operating on inclined surfaces. In fact, spillage problems due to over filled tanks and to fuel shifting when operating on inclined surfaces occurred so regularly that a written warning was routinely prominently displayed on the vehicle in near proximity to the conventional tank's filler neck concerning the dangers of spillage from over filling the conventional tank and from inclined surface operations.
Further, utilizing commercially available fuel cans to refuel the tractor, due to the closeness of the conventional gas filler to an attached grass collection system, frequently resulted in fuel spillage.
Additional problems resulting from the conventional small tractor fuel tank construction along with the conventional location of the filler neck has been the difficulty in utilizing a float-fuel gauge. Without reliable fuel level measuring instruments, which are readily viewable by an operator the risk of running out of fuel in the field is greatly increased. Conventionally, if a fuel gauge were provided with the prior art fuel tank configuration, it was normally a float fuel gauge contained in the filter cap which, due to its position, was not readily viewable by an operator sitting in operators seat.
Accordingly, there is a need for a fuel tank construction which, when installed on a small tractors or the like, virtually eliminates fuel leakage from failed components and significantly reduces fuel spillage during normal tractor operation such as during refueling and operating on inclined surfaces thereby preventing fuel from accumulating on tractor surfaces and which provides for a low fuel sensor easily viewable by the operator to positively warn an operator when the level of fuel in the tank reaches a certain level.